Added repr string for Grouper

Author: tp

pandas/core/groupby.py

@@ -333,6 +333,16 @@ def _set_grouper(self, obj, sort=False):
     def groups(self):
         return self.grouper.groups
 
+    _init_defaults = dict(key=None, level=None, freq=None, axis=0,
+                          sort=False)
+    def __repr__(self):
+        defaults = self._init_defaults
+        attrs = {k: v for k, v in self.__dict__.items()
+                 if k in defaults and v != defaults[k]}
+        attrs = ", ".join("{}={!r}".format(k, v) for k, v in attrs.items())
+        cls_name = self.__class__.__name__
+        return "{}({})".format(cls_name, attrs)
+
 
 class GroupByPlot(PandasObject):
     """

pandas/core/resample.py

@@ -1028,7 +1028,7 @@ def __init__(self, freq='Min', closed=None, label=None, how='mean',
                  convention=None, base=0, **kwargs):
         freq = to_offset(freq)
 
-        end_types = set(['M', 'A', 'Q', 'BM', 'BA', 'BQ', 'W'])
+        end_types = {'M', 'A', 'Q', 'BM', 'BA', 'BQ', 'W'}
         rule = freq.rule_code
         if (rule in end_types or
                 ('-' in rule and rule[:rule.find('-')] in end_types)):
@@ -1286,6 +1286,28 @@ def _get_period_bins(self, ax):
 
         return binner, bins, labels
 
+    # _init_defaults is used in __repr__below
+    _init_defaults = Grouper._init_defaults.copy()
+    _init_defaults.update(freq='Min', how='mean', nperiods=None, axis=0,
+                          fill_method=None, limit=None, loffset=None,
+                          kind=None, convention='e', base=0, sort=True)
+    def __repr__(self):
+        defaults = self._init_defaults.copy()
+        end_types = {'M', 'A', 'Q', 'BM', 'BA', 'BQ', 'W'}
+        rule = self.freq.rule_code
+        if (rule in end_types or
+                ('-' in rule and rule[:rule.find('-')] in end_types)):
+            defaults.update(closed='right', label='right')
+        else:
+            defaults.update(closed='left', label='left')
+
+        attrs = {k: v for k, v in self.__dict__.items()
+                 if k in defaults and v != defaults[k]}
+        attrs['freq'] = attrs['freq'].freqstr
+        attrs = ", ".join("{}={!r}".format(k, v) for k, v in attrs.items())
+        cls_name = self.__class__.__name__
+        return "{}({})".format(cls_name, attrs)
+
 
 def _take_new_index(obj, indexer, new_index, axis=0):
     from pandas.core.api import Series, DataFrame